Hearing loss and cognitive decline: what recent research says

When we think of prevent dementia, we talk about physical activity, diet, or cognitive exercises. A lesser-known factor—and yet one that has been identified as the most important of the modifiable factors in midlife, is the uncorrected hearing loss [1]. Here’s what recent research says, the proposed mechanisms, and what this means in practical terms for Quebecers who want to protect their brain health.

On this page

• What Does Science Say?
• Possible mechanisms
• The ACHIEVE Study
• What this means in everyday life
• The Auditory Journey in Quebec
• Special Case: Seniors and Family Caregivers
• Myths and misconceptions
• Frequently asked questions
• Sources

What Does Science Say?

Visit The Lancet Commission on Dementia Prevention, Intervention, and Care, in its 2020 and 2024 reports, identified 14 modifiable risk factors associated with the risk of dementia. Hearing loss is among the more decisive at midlife (ages 45 to 65), with an estimated population-attributable risk of approximately 7 % [1].

What «population-attributable risk» means»

• This is the theoretical share cases of dementia that could be prevented if a given risk factor were eliminated in the population
• An attributable risk of 7 % for hearing loss means that a significant portion The overall burden of dementia could potentially be reduced if hearing loss in middle age were better treated
• It is one of the most high Among all the identified modifiable risk factors, according to the models, hypertension, smoking, and physical inactivity rank highest
• The estimate is population-based and must be interpreted at the group level, not in relation to an individual

A Few Key Figures to Keep in Mind

• A mild, uncorrected hearing loss is associated with a risk of approximately twice as high cognitive decline
• A moderate loss is associated with a risk of approximately 3 times higher
• A severe loss is associated with a risk of approximately 5 times higher
• Visit hearing loss also doubles the risk of falls among older adults
• A significant part Many Quebecers aged 50 and older already have hearing loss, which they often fail to recognize [2]

To remember

• Visit hearing loss is the most powerful modifiable risk factor for dementia in midlife, according to the Lancet Commission [1]
• The’ACHIEVE study (2023) showed that hearing aids can reduce cognitive decline in high-risk individuals [3]
• Several mechanisms (cognitive overload, sensory deprivation, social isolation, shared vascular factors) may explain this association
• The’early intervention And the hearing protection Lifelong learning is the key driver
• In Quebec, access to a hearing evaluation and to a equipment is regulated by the RAMQ, the OOAQ, and the OAPQ
• Visit active social life remains an independent protective factor that should be maintained

Possible mechanisms

The connection between hearing loss and dementia is probably not the result of a single mechanism, but rather of a combination of factors that interact over time [1][4].

Cognitive Overload

• Compensate Hearing loss requires attentional resources
• These resources are no longer available for memory, language, learning
• In everyday life, this extra effort results in a mental fatigue in group chats
• In the long term, it could contribute to a exhaustion cognitive reserves

Sensory Deprivation

• Visit reduction Auditory stimulation reduces the workload on the brain areas responsible for sound processing
• Several studies have described a volume reduction in certain brain regions in people with uncorrected hearing loss
• Visit brain, like a muscle, seems to benefit from regular stimulation

Social isolation

• Visit difficulty conversing leads to avoiding dinners, outings, and group activities
• The’social isolation is itself an independent risk factor for dementia
• Visit depression, which often follows isolation, also increases the risk of cognitive decline
• Visit interpersonal relationships are a major source of brain stimulation

Shared vascular factors

• The’high blood pressure, diabetes, smoking and vascular disorders affect both the inner ear and the brain
• Visit cochlea and certain regions of the brain share a very fine blood supply that is vulnerable to the same types of damage
• A hearing loss may therefore be, in part, a marker of systemic vascular distress

The ACHIEVE Study

The randomized study ACHIEVE (Aging and Cognitive Health Evaluation in Elders), published in 2023 in The Lancet, shed significant light on the connection between hearing aid and cognitive decline [3]. It is one of the most thorough studies on the subject to date.

The Study Design

• Nearly 1,000 adults people aged 70 to 84 with untreated hearing loss
• Comparison between a group receiving a complete set of hearing aids and a health education group
• Tracking over 3 years
• Evaluation of general cognitive decline using standardized tools
• Population heterogeneous in terms of initial cognitive risk

Key Findings

• Among high-risk individuals cognitive function; the device reduced cognitive decline in nearly half over 3 years
• Profit less pronounced in the low-risk population, but the results are consistent
• Effect observed without significant change other lifestyle habits between the two groups
• Results consistent with the population-based observations previous
• The study reinforces the idea that the’early intervention is a significant intervention for brain health

What This Means in Practice

• Hearing aids are no longer presented solely as a tool comfort or communication
• It is now considered to be a presentation who can help protect cognitive health
• Visit recommendations International organizations (WHO, professional societies) are increasingly incorporating this aspect
• This concept is gaining traction gradually in medical and audiological practice and among the general public

What this means in everyday life

The’practical application Taking advantage of this data involves a few steps that anyone can take, whether in midlife or later in life.

Four Simple Principles

• Don't wait that the loss be significant enough to warrant an assessment
• Consider Fitting hearing aids as soon as indicated, even for mild to moderate hearing loss
• Protect Hearing health throughout life (earplugs, reasonable volume levels, the 60/60 rule for headphones)
• Maintain an active social life despite hearing loss (with or without a hearing aid)

A Hearing Health Routine

• Hearing Evaluation initially around age 50, then every 2 to 3 years if there are no symptoms
• Annual Follow-Up if hearing loss is confirmed or if risk factors are present (diabetes, high blood pressure, occupational exposure to noise)
• Protection in noisy environments (concerts, snowmobiles, power tools, firearms, clubs, parties)
• Limit the duration of exposure to noise levels exceeding 85 dB
• Lifestyle overall protective factors: physical activity, sleep, diet, tobacco, alcohol
• Cognitive stimulation regular activities (reading, conversation, languages, music, games, community involvement)

When to seek help quickly

• Sudden Hearing Loss, especially on one side (emergency)
• Tinnitus sudden, throbbing, or one-sided
• Dizziness associated with hearing loss
• Earache persistent ear discharge
• Head Injury recent, with changes in hearing
• Perceived cognitive decline or a complaint of memory loss associated with difficulty understanding

The Auditory Journey in Quebec

In Quebec, the audio tour involves a variety of professionals and service levels, in both the public and private sectors. Understanding this well helps to take early action, which is precisely what is at stake when it comes to cognitive health.

Who Does What

• Family doctor : initial evaluation for hearing loss, removal of earwax plugs, treatment of ear infections, review of potentially ototoxic medications, referral
• Audiologist (registered with the OOAQ): audiological evaluation and diagnosis, monitoring of tinnitus and vestibular disorders [5]
• Hearing Aid Specialist (registered with the OAPQ): selection, fitting, and follow-up of hearing aids [6]
• ENT (otolaryngologist): specific conditions (sudden hearing loss, Ménière's disease, acoustic neuroma, otosclerosis), surgery

Coverage and Access

• Direct Access audiology services available in Quebec without a required doctor's referral
• Evaluation Covered in certain cases (public institutions, doctor's referral, specific conditions)
• Hearing Aids covered by the RAMQ for individuals who are eligible under the program's criteria [7]
• Private Sector often faster for evaluating and selecting hearing aids
• Group insurance that partially cover the cost of prosthetics under several plans

Are you or a loved one concerned about hearing loss? Omicron Clinic offers initial medical evaluations for hearing loss, earwax removal, treatment for ear infections, reviews of potentially ototoxic medications, and prompt referrals to audiology or ENT specialists when necessary at our locations in Quebec. Make an appointment or opt for the teleconsultation for a first assessment.

Special Case: Seniors and Family Caregivers

Visit seniors and their family caregivers are often the first to be affected by this connection between hearing and cognition. The shared vigilance is one of the best ways to identify an uncorrected loss.

Signs that those around the person notice before the person does

• Volume very high on television or the radio
• Repeated requests for repeat the same sentence
• Answers that do not match to the question, especially in noisy environments
• Avoidance family dinners or social activities
• Fatigue and irritability after group meetings
• Phone used less than before
• Complaint that people «mumble» or speak too fast

A Helpful Approach for Families

• Speaking Openly based on what we observe, without overreacting
• Proposer A hearing screening as part of a routine preventive exam after age 50
• Accompany to a medical or audiology appointment, if the person wishes
• Support The first few weeks of adjusting to a hearing aid
• Encourage outings, face-to-face conversations, and social activities
• Discuss with the doctor if the hearing loss is accompanied by memory problems

If your memory starts to become a concern

• Do not assign automatically leads to confusion at that age
• Check first Hearing: Untreated hearing loss can give the impression of cognitive decline (delayed responses, fatigue, isolation)
• Request a hearing evaluation and a medical evaluation to get the full picture
• Consider other modifiable factors identified by the Lancet Commission (high blood pressure, diabetes, depression, physical inactivity)
• Refer to a geriatric clinic or memory clinic if concerns persist

Myths and misconceptions

«Hearing loss has nothing to do with memory»

False, according to recent data. The Lancet Commission lists hearing loss among the primary modifiable risk factors midlife dementia [1]. Several plausible mechanisms have been described. This association does not mean that everyone with hearing loss will develop dementia, but rather that early intervention is a significant factor in cognitive prevention at the population level.

«If I'm having trouble hearing, it's just my age—there's nothing I can do about it.»

False. Age-related hearing loss is common as people age, but it can be assessed, monitored, and compensated for. The idea that ’we don’t do anything about it because it’s just part of aging« no longer aligns with current recommendations, especially given the potential impact on cognition, safety (falls), mood, and social life.

«Hearing aids are only useful for severe hearing loss.»

False. The ACHIEVE study and other recent data suggest that the’early intervention, even in cases of mild to moderate weight loss, is associated with best results in terms of communication, well-being, and possibly cognition [3]. The later the hearing aid is fitted, the more effort the brain must exert to readjust.

«A hearing aid provides complete protection against dementia»

False. No single intervention «completely protects» against dementia. Hearing aids are part of a set of levers (physical activity, diet, sleep, tobacco use, alcohol consumption, high blood pressure, diabetes, depression, social life, cognitive stimulation). Its purpose is to complement these factors, not to replace them.

«Having a hearing test means they're going to make me get hearing aids.»

False. A hearing test is a evaluation, not a requirement for treatment. The decision to fit a hearing aid is then made in consultation with the hearing care professional, taking into account the test results, the clinical implications, and the individual’s preferences. Mild hearing loss may be monitored without immediate fitting of a hearing aid.

Frequently asked questions

At what age should you have a hearing test to protect your cognitive function?

An initial baseline evaluation around age 50, followed by evaluations every 2 to 3 years in the absence of symptoms, is a reasonable approach. If risk factors are present (occupational exposure to noise, diabetes, high blood pressure, or a family history of early-onset hearing loss) or if there are signs of hearing loss, earlier and more frequent evaluations are recommended.

If I'm already wearing a device, am I «protected»?

Wearing a properly fitted hearing aid and using it daily helps reduce the main mechanisms described (cognitive overload, isolation, sensory deprivation). This is not an absolute protection against dementia, but one of several favorable factors. Regular follow-up with an audiologist is essential to maintain this effectiveness.

Do you need a referral to get a hearing test in Quebec?

No. In Quebec, you can see an audiologist directly without a doctor’s referral. A preliminary medical consultation is still recommended in cases of pain, discharge, sudden hearing loss, or to rule out earwax buildup and infection. However, some insurance plans or certain RAMQ coverage options require a referral for reimbursement.

What if you already have mild cognitive decline?

A hearing screening is still recommended. Uncorrected hearing loss can make cognitive decline appear to be present more important than it actually is (delayed responses, isolation, fatigue). Hearing aids help provide a more accurate assessment of actual cognitive function and improve communication with family members and caregivers.

Is there a risk in waiting a few years before taking action?

Yes. The longer it takes to correct hearing loss, the more the’brain adaptation is a long and demanding process. Several studies suggest that cognitive and functional benefits are more pronounced when hearing aids are fitted early. According to current data, waiting until there is «significant hearing loss» before taking action is no longer the best strategy.

What percentage of all recommendations for preventing dementia focus on hearing health?

Hearing health prevention is one of the the most powerful modifiable risk factors at midlife, but it is part of a broader set of measures: physical activity, sleep, diet, blood pressure and diabetes management, smoking cessation, moderate alcohol consumption, treatment for depression, cognitive stimulation, and social engagement. The strength of the Lancet Commission’s model lies in identifying several cumulative levers, each of which is beneficial.

Sources

1. Livingston G. et al. Dementia Prevention, Intervention, and Care: Lancet Commission (2020, 2024).
2. World Health Organization (WHO). World Report on Hearing.
3. Lin FR. et al. ACHIEVE Trial — Hearing Aids and Cognitive Decline, The Lancet 2023.
4. Alzheimer Society of Canada. Modifiable Risk Factors for Dementia.
5. Quebec Order of Speech-Language Pathologists and Audiologists (OOAQ). The Role of the Audiologist in Quebec.
6. Quebec Order of Audiologists (OAPQ). The Role of the Audiologist and Hearing Aids.
7. RAMQ — Quebec Health Insurance Board. Hearing Aid Program.
8. INSPQ — National Institute of Public Health of Quebec. Aging, Hearing, and Public Health.

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